Download or read book The Many Phases of Massive Galaxies written by Mariska Therese Kriek and published by . This book was released on 2007 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Galaxies written by Francoise Combes and published by John Wiley & Sons. This book was released on 2021-03-05 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxies are vast ensembles of stars, gas and dust, embedded in dark matter halos. They are the basic building blocks of the Universe, gathered in groups, clusters and super-clusters. They exist in many forms, either as spheroids or disks. Classifications, such as the Hubble sequence (based on mass concentration and gas fraction) and the colormagnitude diagram (which separates a blue cloud from a red sequence) help to understand their formation and evolution. Galaxies spend a large part of their lives in the blue cloud, forming stars as spiral or dwarf galaxies. Then, via a mechanism that is still unclear, they stop forming stars and quietly end in the red sequence, as spheroids. This transformation may be due to galaxy interactions, or because of the feedback of active nuclei, through the energy released by their central super-massive black holes. These mechanisms could explain the history of cosmic star formation, the rate of which was far greater in the first half of the UniverseÂs life. Galaxies delves into all of these surrounding subjects in six chapters written by dedicated, specialist astronomers and researchers in the field, from their numerical simulations to their evolutions.
Download or read book Star Formation Rates of Galaxies written by Andreas Zezas and published by Cambridge University Press. This book was released on 2021-04-29 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: Star-formation is one of the key processes that shape the current state and evolution of galaxies. This volume provides a comprehensive presentation of the different methods used to measure the intensity of recent or on-going star-forming activity in galaxies, discussing their advantages and complications in detail. It includes a thorough overview of the theoretical underpinnings of star-formation rate indicators, including topics such as stellar evolution and stellar spectra, the stellar initial mass function, and the physical conditions in the interstellar medium. The authors bring together in one place detailed and comparative discussions of traditional and new star-formation rate indicators, star-formation rate measurements in different spatial scales, and comparisons of star-formation rate indicators probing different stellar populations, along with the corresponding theoretical background. This is a useful reference for students and researchers working in the field of extragalactic astrophysics and studying star-formation in local and higher-redshift galaxies.
Download or read book Formation and Evolution of Galaxies and Large Structures in the Universe written by J. Audouze and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 441 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the NATO Advanced Study Institute, La Plagne, France, March, 1983
Download or read book Star Formation and the Evolution of Massive Galaxies Across Cosmic Time written by Jamie Richard Ownsworth and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Formation of Massive Galaxies written by and published by . This book was released on 2008 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Evolution of Galaxies written by Marc Sauvage and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 563 pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxies have a history. This has become clear from recent sky surveys which have shown that distant galaxies, formed early in the life of the Universe, differ from the nearby ones. New observational windows at ultraviolet, infrared and millimetric wavelengths (provided by ROSAT, IRAM, IUE, IRAS, ISO) have revealed that galaxies contain a wealth of components: very hot gas, atomic hydrogen, molecules, dust, dark matter ... A significant advance is expected due to new instruments (VLT, FIRST, XMM) which will allow one to explore the most distant Universe. Three Euroconferences have been planned to punctuate this new epoch in galactic research, bringing together specialists in various fields of Astronomy.
Download or read book Probing Galaxy Evolution by Unveiling the Structure of Massive Galaxies Across Cosmic Time and in Diverse Environments written by Timothy Weinzirl and published by Springer. This book was released on 2014-07-17 with total page 249 pages. Available in PDF, EPUB and Kindle. Book excerpt: Awarded the American Astronomical Society (AAS) Rodger Doxsey Travel Prize, and with a foreword by thesis supervisor Professor Shardha Jogee at the University of Texas at Austin, this thesis discusses one of the primary outstanding problems in extragalactic astronomy: how galaxies form and evolve. Galaxies consist of two fundamental kinds of structure: rotationally supported disks and spheroidal/triaxial structures supported by random stellar motions. Understanding the balance between these galaxy components is vital to comprehending the relative importance of the different mechanisms (galaxy collisions, gas accretion and internal secular processes) that assemble and shape galaxies. Using panchromatic imaging from some of the largest and deepest space-based galaxy surveys, an empirical census of galaxy structure is made for galaxies at different cosmic epochs and in environments spanning low to extremely high galaxy number densities. An important result of this work is that disk structures are far more prevalent in massive galaxies than previously thought. The associated challenges raised for contemporary theoretical models of galaxy formation are discussed. The method of galaxy structural decomposition is treated thoroughly since it is relevant for future studies of galaxy structure using next-generation facilities, like the James Webb Space Telescope and the ground-based Giant Magellan Telescope with adaptive optics.
Download or read book Unveiling Galaxies written by Jean-René Roy and published by Cambridge University Press. This book was released on 2018 with total page 311 pages. Available in PDF, EPUB and Kindle. Book excerpt: A thought provoking study of the powerful impact of images in guiding astronomers' understanding of galaxies through time.
Download or read book Galaxies at High Redshift written by I. Pérez-Fournon and published by Cambridge University Press. This book was released on 2003-03-20 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents lectures of the XI Canary Islands Winter School of Astrophysics written by experts in the field.
Download or read book Probing Galaxy Evolution by Unveiling the Structure of Massive Galaxies Across Cosmic Time and in Diverse Environments written by Timothy Michael Weinzirl and published by . This book was released on 2014-08-31 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Evolution of Massive Galaxies written by Kristen Leah Shapiro and published by . This book was released on 2010 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: Galaxies, as the fundamental building blocks of the Universe, are the critical link between the overall evolution of the Universe and the assembly of small-scale structures, such as stars and planets, within it. Unfortunately, the formation and evolution of galaxies remains poorly understood, due to the incredible complexity of the physics that governs these processes. To study and constrain these processes, a particularly useful galaxy population are bulge-dominated galaxies such as elliptical and large spiral galaxies, which together are the most massive and most evolved components of the local Universe. In the present day, these galaxies are dominated by old stars; however, their histories likely include an epoch of powerful star formation and rapid growth of their supermassive black holes. Progress in understanding the evolution of massive galaxies can therefore proceed on two fronts -- 1) observations of their formation in situ in the early Universe, and 2) detailed studies of the fossil relics of this process in the local Universe -- with the ultimate goal being to link progenitors and descendants. A key epoch for such investigations is 10 billion years ago, the most active period in the Universe's history, at which time the vast majority of stellar material in galaxies was assembled. Recent comparisons of the observed properties of galaxy populations across cosmic time have shown that the dominant star-forming galaxy population at these early times were the probable ancestors of present-day massive (bulge-dominated spiral and elliptical) galaxies. The obvious direction for current and future research is therefore to probe the detailed evolution with time of the properties and sub-structures that define this local galaxy population. This goal has guided my dissertation research, as described in the following pages. Using photometric, spectroscopic, and integral-field observations at optical through mid-infrared wavelengths, I have studied both star-forming galaxies in the early Universe and their present-day descendants. Specifically, this thesis explores the dynamical, star-forming, and black hole properties of galaxies 10 billion years ago and shows that these young galaxies must be assembled via a rapid but steady influx of gas from the surrounding cosmic structure. The resulting large quantity of gas in these galaxies causes super-large star-forming gas clouds to form, and the dynamical interactions of these clouds control the evolution of the galaxies' supermassive black holes and internal sub-structures, producing the bulges and globular cluster populations observed in the present day. Studies of the resulting local massive galaxy population, also presented herein, confirm that such successive minor dynamical disturbances were important to the assembly of these bulge-dominated galaxies and their supermassive black holes. In the pages of this thesis, an exciting link is emerging in which many observed properties of local galaxies can be explained by the dramatic internal processes occurring in galaxies 10 billion years ago, during the era of the most rapid galaxy assembly.
Download or read book Outskirts of Galaxies written by Johan H. Knapen and published by Springer. This book was released on 2017-07-09 with total page 367 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book consists of invited reviews written by world-renowned experts on the subject of the outskirts of galaxies, an upcoming field which has been understudied so far. These regions are faint and hard to observe, yet hide a tremendous amount of information on the origin and early evolution of galaxies. They thus allow astronomers to address some of the most topical problems, such as gaseous and satellite accretion, radial migration, and merging. The book is published in conjunction with the celebration of the end of the four-year DAGAL project, an EU-funded initial training network, and with a major international conference on the topic held in March 2016 in Toledo. It thus reflects not only the views of the experts, but also the scientific discussions and progress achieved during the project and the meeting. The reviews in the book describe the most modern observations of the outer regions of our own Galaxy, and of galaxies in the local and high-redshift Universe. They tackle disks, haloes, streams, and accretion as observed through deep imaging and spectroscopy, and guide the reader through the various formation and evolution scenarios for galaxies. The reviews focus on the major open questions in the field, and explore how they can be tackled in the future. This book provides a unique entry point into the field for graduate students and non-specialists, and serves as a reference work for researchers in this exciting new field.
Download or read book Probing the Evolution of the Most Massive Galaxies written by Stewart William Buchan and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Joint Evolution of Black Holes and Galaxies written by M. Colpi and published by CRC Press. This book was released on 2006-01-27 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt: Black holes are among the most mysterious objects that the human mind has been capable of imagining. As pure mathematical constructions, they are tools for exploiting the fundamental laws of physics. As astronomical sources, they are part of our cosmic landscape, warping space-time, coupled to the large-scale properties and life cycle of their host
Download or read book The Clustering of Massive Galaxies in the Early Universe written by Ryan F. Quadri and published by . This book was released on 2007 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigating the Stellar Mass Growth and Quiescence of Massive Galaxies In the Early Universe Using Wide field Imaging written by Matthew Louis Stevans (Jr.) and published by . This book was released on 2019 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: While galaxies formed stars most actively around z=2, or ~3 Gyr after the Big Bang, when the universal star formation density in the universe peaked. By this time a population of massive galaxies had already formed 1011 - 1012 [solar mass] of stars and some had their star-formation shut off in a process known as quenching. Understanding how these massive galaxies build up their stellar mass and then quench so early in the universe is a fundamental observational test of galaxy evolution. If not obscured by dust, massive galaxies are very bright, and can be observed in the optical and infrared (IR) to probe their redshifted ultraviolet (UV) and optical emission, respectively. The UV emission is produced by newly formed O and B type stars within 100 Myrs of forming, while the rest-frame optical light is produced by stars of all type and traces the stellar mass in the galaxy. By measuring the UV and optical output of galaxies, astronomers can derive star-formation rates and stellar masses. Measuring these properties for large samples of galaxies across a wide dynamic range provides benchmarks for simulations of galaxy formation and evolution physics. The work in this dissertation focuses on completing a wide field imaging survey of galaxies with high UV star-formation rates and high stellar masses at high redshift to perform the most statistically robust census to date. In Chapter 1 we motivate measuring the UV output and the quiescent fraction of high-redshift galaxies. To measure the UV output of massive star-forming galaxies at high redshift we utilize an extensive multi-wavelength dataset assembled in the Spitzer HETDEX Exploratory Large Area Survey (SHELA) Field. The data set includes five bands of deep optical imaging from the Dark Energy Camera (DECam), deep 3.6 micron and 4.5 micron imaging for Spitzer, and J and K [subscript s] imaging for the VISTA-CFHT Stripe 82 (VICS82) Near-infrared Survey. Our extensive dataset compiled from both ground and space-based observatories is uniquely capable of studying the most actively star-forming galaxies which are often very massive galaxies residing in the rarest high-sigma density peaks of the cosmic web. In Chapter 2 we study the bright end of the z=4 galaxy UV luminosity distribution or luminosity function by fitting the spectral energy distributions (SEDs) of the galaxies in our photometric data with Stellar Population Synthesis (SPS) models to measure the galaxies' redshifts and UV luminosity. In addition to measuring the bright end of the galaxy luminosity function, we had the unanticipated result of measuring the faint end of the z=4 active galactic nuclei (AGN) UV luminosity function, which has implications on the contribution of AGNs during the end of the reionization era. We compare our observed galaxy luminosity function to luminosity functions predicted by semi-analytical models (SAMs) with different prescriptions for star formation physics, such as the density of neutral hydrogen. We find our observations are consistent with predictions that galaxies at z=3-4 form stars more efficiently than at lower redshifts due to shorter neutral hydrogen depletion times. In Chapter 3, we measure the fraction of massive (M [subscript *] > 1011 [solar mass] galaxies at z=3-5 in the largest volume to date. To do this we produce a K [subscript s] -selected catalog by combining deep K [subscript s] -band imaging from the NEWFIRM HETDEX survey (NHS), which we obtain, reduce, and catalog. We select quiescent galaxies by performing SED-fitting with SPS models to measure their redshifts, SFRs, and stellar masses. We define quiescent galaxies as having a specific SFR (sSFR; sSFR = SFR / stellar mass)
